AM Subsystem
Parameter
Typical Return
{ON|1|OFF|0}
0 (OFF) or 1 (ON)
Set AM to DSSC mode:
AM:DSSC ON
l
The power-on default value is OFF.
l
In DSSC AM, zero modulation results in zero output signal, and increasing modulation input signal raises the ampli-
tude of the sidebands in proportion to the amplitude of the modulating signal.
l
DSSC AM is useful for some digital modulation modes.
l
In "normal" AM, zero modulation results in a half-amplitude carrier wave signal being output. As modulation input
signal rises, the carrier is amplitude modulated between 0 and 100% amplitude.
l
In DSSC, the
setting applies, and scales the modulation signal from 0 to 120% modulation.
[SOURce[1|2]:]AM:INTernal:FREQuency {<
frequency
>|MINimum|MAXimum}
[SOURce[1|2]:]AM:INTernal:FREQuency? [{MINimum|MAXimum}]
Sets frequency of modulating waveform. The waveform chosen as modulating source will operate at that frequency,
within waveform frequency limits.
Parameter
Typical Return
1 μHz to the maximum allowed for the internal function. Default 100 Hz
+1.00000000004
Set the modulating frequency to 10 kHz:
AM:INT:FUNC 10000
l
When you select an arbitrary waveform as the modulating source, the frequency changes to the frequency of the
arbitrary waveform, based on the sample rate and the number of points in the arbitrary waveform.
l
When using an arbitrary waveform for the modulating source, changing this parameter also changes the cached
metadata representing the aribtrary waveform's sample rate. You can also change the modulating frequency of an
arbitrary waveform with
, and
. These commands and the modulation frequency command are directly coupled in order to
keep the arbitrary waveform behaving exactly as it was last played. If you later turn modulation off and select that
same arbitrary waveform as the current function, its sample rate (and corresponding frequency based upon the
number of points) will be the same as it was when played as the modulation source.
l
If the internal function is TRIangle, RAMP, or NRAMp, the maximum frequency limited to 200 kHz. If the internal
function is PRBS, the frequency refers to bit rate and is limited to 50 Mbps.
l
This command should be used only with the internal modulation source (
).
[SOURce[1|2]:]AM:INTernal:FUNCtion <
function
>
[SOURce[1|2]:]AM:INTernal:FUNCtion?
Selects shape of modulating waveform.
158
Agilent 33500 Series Operating and Service Guide
